Field of the Invention
The present invention relates to a fuel supply system of a diesel engine. More particularly, the present invention relates to a fuel filter for a diesel engine for filtering diesel fuel that is supplied from a fuel tank to a diesel engine.
Description of Related Art
In general, a diesel fuel filter is formed in a diesel fuel supply system for supplying diesel fuel that is stored at a fuel tank to a diesel engine.
The diesel fuel filter filters diesel fuel that is supplied from the fuel tank to the diesel engine, filters impurities that are included in the diesel fuel, heats the diesel fuel so it does not coagulate, and separates moisture that is contained in the diesel fuel to discharge the moisture to the outside.
Such a diesel fuel filter basically includes a housing, a filter that is housed in the housing, a head cover that is coupled to an upper portion of the housing, and a heater that is installed between the filter and the head cover.
Further, the diesel fuel filter includes a thermo switch that is installed at the head cover side and that applies a switching signal to a heater according to a temperature of diesel fuel, a moisture sensor that detects a water level of moisture and that is stored at a housing, and a drain plug that is installed in a lower portion of the housing and that discharges moisture within the housing.
The diesel fuel filter is generally mounted in a vehicle body through a mounting unit, for example, in the diesel fuel filter, the head cover side is located at the upper side of a cowl panel, and the housing side is located at a brake booster side.
However, a conventional diesel fuel filter having the foregoing configuration includes an outer nipple, a thermo switch, a sensor circuit, and a connector that are mounted in a vehicle body and that are protruded to the outside of a housing in a head cover, and thus structural robustness thereof is weak, and when a vehicle offset-collides, the diesel fuel filter may be damaged by the collision force.
Further, since the conventional diesel fuel filter includes an outer nipple, a thermo switch, a sensor circuit, and a connector that are protruded to the outside of a housing at a head cover, there is a drawback that it is difficult to set a layout in a design step, and the conventional diesel fuel filter has disadvantageous in assembly workability and maintainability because of peripheral components.
In order to operate a heater, because a conventional diesel fuel filter should have a thermo switch that applies a switching signal to the heater according to a temperature of diesel fuel, an entire structure of the diesel fuel filter is complicated and the number of assembly components increases, and thus an assembly failure may occur and production cost and weight may increase.
Further, because the conventional diesel fuel filter adapts a method of exchanging a cartridge including a filter and a housing as regular exchange components, environment pollution may occur due to disposal of the cartridge.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.